Add indexing for faster queries

Author: Leo7Deng

backend/postgres/migrations/000003_init.down.sql

@@ -1,2 +1,3 @@
 DROP TABLE IF EXISTS users_circles;
 DROP TABLE IF EXISTS circles;
+DROP INDEX IF EXISTS idx_users_circles_user_id;

backend/postgres/migrations/000003_init.up.sql

@@ -14,3 +14,9 @@ CREATE TABLE users_circles (
     FOREIGN KEY (circle_id) REFERENCES circles(id) ON DELETE CASCADE,
     UNIQUE (user_id, circle_id)
 );
+
+CREATE INDEX idx_users_circles_user_id
+  ON users_circles(user_id);
+
+CREATE INDEX idx_users_circles_circle_id
+  ON users_circles(circle_id);

backend/postgres/migrations/000004_init.down.sql

@@ -1 +1,2 @@
-DROP TABLE IF EXISTS messages;
+DROP TABLE IF EXISTS messages;
+DROP INDEX IF EXISTS idx_messages_circle_date;

backend/postgres/migrations/000004_init.up.sql

@@ -4,4 +4,7 @@ CREATE TABLE messages (
     author_id INT NOT NULL,
     created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
     content TEXT NOT NULL
-);
+);
+
+CREATE INDEX idx_messages_circle_date
+  ON messages(circle_id, created_at DESC);

backend/postgres/migrations/000005_init.down.sql

@@ -1,2 +1,2 @@
 DROP FUNCTION IF EXISTS search_circle_messages(INT, TEXT);
-DROP FUNCTION IF EXISTS get_users_in_circle(INT, INT);
+DROP FUNCTION IF EXISTS get_users_in_circle(INT, INT);